The RCCNZ has since organised two extensive sea-based searches based on different scenarios, covering a combined area of 500,000 square nautical miles.
This morning, a shoreline search is being undertaken, based on a third scenario.
"We have tasked a twin-engine fixed-wing aircraft to search the shoreline and coast starting at Tauroa Point, searching along 90 Mile Beach, north of Northland, and out to and around Three Kings Islands," said mission controller Neville Blakemore.
"While we have grave concerns for the crew on board Nina, we have not given up hope of finding survivors."
The Hamilton-based Phillips Search and Rescue Trust fixed-wing aeroplane Piper Chieftain with the pilot and three observers on board will conduct a search for survivors, the liferaft Nina was carrying, or any wreckage or debris from the schooner.
The plane is able to search for approximately seven hours.
The 84-year-old wooden vessel, owned by American David Dyche, 58, was heading for Newcastle, Australia.
Mr Dyche was travelling with his 60-year-old wife, Rosemary, their son David, 17, a 35-year-old British man and a well-known maritime technology expert Evi Nemeth, 73.
An 18-year-old American woman and 28-year-old American man were also on board.
They left the Bay of Islands on May 29.
A text from Ms Nemeth, sent on June 4 to New Zealand meteorologist Bob McDavitt, was the last known communication from the vessel when it was about 370 nautical miles west-north-west of Cape Reinga.
RCCNZ says the Nina is equipped with satellite phone, a spot device which allows regular tracking signals to be sent manually, and an emergency beacon. The emergency beacon has not been activated.
RCCNZ search and rescue mission coordinator Kevin Banaghan said an RNZAF P3 Orion had completed two extensive searches.
On Tuesday, a search area of 160,000 square nautical miles was covered, to the immediate north-north-east of New Zealand, based on the vessel being disabled and drifting.
The following day, a search was completed of 324,000 square nautical miles between northern New Zealand and the Australian coast, based on the vessel suffering damage but continuing to make progress towards Australia.
To date, no sign of the vessel has been found.
Records show that conditions at the last known position for the vessel, on June 4, were very rough, with winds of 80km/h, gusting to 110km/h, and swells of up to 8 metres.
"We do hold grave concerns for the Nina and her crew but remain hopeful of a positive outcome," a spokesman for RCCNZ said.
"RCCNZ is liaising with the Australian Maritime Safety Authority (AMSA), and will continue to review search options."
